1. Wildlife Biology Program, University of Montana, 32 Campus Drive, Missoula, Montana 59812, USA
2. Alaska Department of Fish and Game, 1300 College Road, Fairbanks, Alaska 99701-1599, USA
3. Center for Conservation Medicine, School of Veterinary Medicine, Tufts University, 200 Westboro Road, North Grafton, Massachusetts 01536, USA
4. Colorado Division of Wildlife, 317 W. Prospect Road, Fort Collins, Colorado 80523, USA
5. Current address: National Park Service, Biological Resource Management Division, 1201 Oak Ridge Drive, Suite 200, Fort Collins, Colorado 80625, USA
6. Forest Sciences Laboratory, Rocky Mountain Research Station, 800 E. Beckwith, Missoula, Montana 59807, USA
7. Division of Biological Sciences, University of Montana, 32 Campus Drive, Missoula, Montana 59812, USA